Aphthoid ulcers in Crohn disease

Double contrast barium enema demonstrates small aphthoid ulcers in a patient with early Crohn disease of the colon (arrows). Barium has collected in the superficial erosions, which are surrounded by edematous mucosa. These small erosions, less typically seen in ulcerative colitis, are the precursors of larger discrete ulcers, fistulae, and sinus tracts.